As a kind of berry food rich in flavonoids,the determination method of total flavonoids content of Aronia melanocarpa is of great significance.This paper compares the applicability of NaNO_(2)-Al(NO_(3))_(3)-NaOH colo...As a kind of berry food rich in flavonoids,the determination method of total flavonoids content of Aronia melanocarpa is of great significance.This paper compares the applicability of NaNO_(2)-Al(NO_(3))_(3)-NaOH colorimetry and AlCl_(3)colorimetry to total flavonoids content of the exocarp of Aronia melanocarpa by Ultraviolet-visible Spectrophotometry.At the same time,we determined hydroxyl radical(OH·-)inhibition rate,superoxide anion radical(O_(2)·-)inhibition rate and 1,1-diphenyl-2-picrylhydrazyl radical free radical(DPPH·)scavenging rate of total flavonoids extracted from Aronia melanocarpa.It is found that AlCl_(3)colorimetry has good repeatability,precision,and accuracy.The method is suitable for the determination of total flavonoids in the exocarp of Aronia melanocarpa.Thus,by the established method the content of total flavonoids in the exocarp of Aronia melanocarpa was determined as high as(36.711±0.034)mg/g.The results of antioxidant activity showed superoxide anion radical scavenging ability,hydroxyl radical scavenging ability and DPPH radical scavenging ability of the total flavonoids extract reached 45.33%,87.87%and 98.05%,respectively,indicating that it had good antioxidant activity.展开更多
以银杏外种皮为原料,用乙醇为溶剂提取其中的酚类化合物,研究银杏外种皮多酚(polyphenol exocarp of ginkgo biloba,PEGB)粗提物的乙醇提取工艺条件及抗氧化性能。选择乙醇体积分数、浸提时间、浸提温度、料液比四个因素进行单因素实验...以银杏外种皮为原料,用乙醇为溶剂提取其中的酚类化合物,研究银杏外种皮多酚(polyphenol exocarp of ginkgo biloba,PEGB)粗提物的乙醇提取工艺条件及抗氧化性能。选择乙醇体积分数、浸提时间、浸提温度、料液比四个因素进行单因素实验,通过响应面法进一步优化提取条件。结果表明,最佳提取工艺条件为乙醇浓度70%,浸提时间2.6h,浸提温度90℃,料液比1∶30,此条件下多酚的提取率为5.33mg GAE/g。PEGB粗提物对DPPH自由基和羟基自由基的清除能力随浓度升高而增强。当PEGB粗提物浓度为0.5mg/mL时,对DPPH的清除率为84.25%,对羟基自由基的清除率为78.89%,表明高浓度的PEGB粗提物具有较强的抗氧化性能。展开更多
文摘As a kind of berry food rich in flavonoids,the determination method of total flavonoids content of Aronia melanocarpa is of great significance.This paper compares the applicability of NaNO_(2)-Al(NO_(3))_(3)-NaOH colorimetry and AlCl_(3)colorimetry to total flavonoids content of the exocarp of Aronia melanocarpa by Ultraviolet-visible Spectrophotometry.At the same time,we determined hydroxyl radical(OH·-)inhibition rate,superoxide anion radical(O_(2)·-)inhibition rate and 1,1-diphenyl-2-picrylhydrazyl radical free radical(DPPH·)scavenging rate of total flavonoids extracted from Aronia melanocarpa.It is found that AlCl_(3)colorimetry has good repeatability,precision,and accuracy.The method is suitable for the determination of total flavonoids in the exocarp of Aronia melanocarpa.Thus,by the established method the content of total flavonoids in the exocarp of Aronia melanocarpa was determined as high as(36.711±0.034)mg/g.The results of antioxidant activity showed superoxide anion radical scavenging ability,hydroxyl radical scavenging ability and DPPH radical scavenging ability of the total flavonoids extract reached 45.33%,87.87%and 98.05%,respectively,indicating that it had good antioxidant activity.
